1. Technical Field
The present invention relates to a liquid ejecting apparatus provided with a liquid ejecting head capable of ejecting a liquid from a plurality of nozzles while moving reciprocally relative to a medium such as paper.
2. Related Art
In the related art, an ink jet printer (hereinafter also referred to simply as “a printer”) which performs printing on a medium such as paper by ejecting an ink (an example of a liquid) from a plurality of nozzles of a liquid ejecting head is widely known as a liquid ejecting apparatus which ejects a liquid onto a medium such as paper. Among such printers, there is a printer in which the liquid ejecting head is rendered capable of reciprocal movement in a scanning direction which orthogonally intersects a transport direction of the paper, and the printer has a printing mode in which bidirectional printing in which the ink is ejected onto the paper in both an outward motion and a return motion of the liquid ejecting head is performed.
In this type of printer, an image is formed (printed) due to ink droplets which are ejected from the nozzles of the liquid ejecting head during both the outward motion and the return motion landing on the paper in pixel positions which are set at a fixed pitch in the scanning direction. Therefore, in order to obtain a clear printed image in the printer, when the same pixel position in the scanning direction is set as a target, it is necessary to cause the landing position in the scanning direction of the ink droplets which land on the paper to match during the outward motion and during the return motion of the liquid ejecting head.
However, in the bidirectional printing in which the liquid ejecting head moves in opposite directions during the outward motion and the during return motion, a flight path of an ink droplet which is ejected vertically toward the surface of the medium from the liquid ejecting head which moves adopts a diagonal path which inclines to the opposite side alternately during the outward motion and during the return motion due to the influence of a speed vector in a movement direction of the liquid ejecting head. Therefore, in the bidirectional printing, the ejection timing (the ejection position) during the outward motion and during the return motion of the liquid ejecting head is adjusted using a correction value (an adjustment value). However, even if an appropriate correction value is set when the printer is shipped, there is a case in which the value of the correction value becomes inappropriate due to degradation with the passage of time or the like and print shifting in the scanning direction between during the outward motion and during the return motion of the liquid ejecting head occurs.
Therefore, in a printer (a print control device) disclosed in JP-A-2002-292959, for example, a test pattern containing a plurality of inspection patterns (for example, ruled line pairs) in which the shift amounts of the landing positions of the ink droplets differ is printed onto the paper during the outward motion and the return motion of the liquid ejecting head. A Bi-D adjustment in which the correction value (the adjustment value) for the bidirectional printing is updated to an appropriate value is performed by inputting selection data such as a number corresponding to the inspection pattern with the smallest shift amount from the printed result of the test pattern to the printer by operating an operation unit.
Incidentally, in a printer which has a plurality of printing modes in which the movement speed of the liquid ejecting head differs, the correction value (the adjustment value) during the bidirectional printing differs for each of the plurality of printing modes. Therefore, in the printer disclosed in JP-A-2002-292959, it is necessary to perform Bi-D adjustment work in which a test pattern is printed, and one condition with the smallest print shifting from the printed result of the test pattern is selected and set for each printing mode with a different carriage speed.